The effects of silver ions and silver nanoparticles on cell division and expression of cdc2 gene in Allium cepa root tips

2018 ◽  
Vol 62 (1) ◽  
pp. 166-172 ◽  
Author(s):  
A. S. Fouad ◽  
R. M. Hafez
2017 ◽  
Vol 137 ◽  
pp. 18-28 ◽  
Author(s):  
Petra Cvjetko ◽  
Anita Milošić ◽  
Ana-Marija Domijan ◽  
Ivana Vinković Vrček ◽  
Sonja Tolić ◽  
...  

Author(s):  
Nishita Gogia ◽  
Anandhi D ◽  
Kanaga G ◽  
Revathi K

The scope of the present study was to evaluate the In-vitro biological potential of Green synthesized silver nanoparticles from Chromolaena odorata, Caesalpinia coriaria (Bark) and Caesalpinia coriaria (Leaf). We investigated the effect of green synthesized silver nanoparticles from Chromolaena odorata, Caesalpinia coriaria (Bark) and Caesalpinia coriaria (Leaf) by studying anti-mitotic activity An attempt has been made to evaluate the anti-mitotic activity of silver nanoparticles using Allium cepa roots. The mitotic index of the root tips meristem was calculated and compared with the standard methotrexate. Antimitotic activity results shows the mitotic index was ranged from 30-40%. Green synthesized silver nanoparticles from Chromolaena odorato, Caesalpinia coriaria (Bark) and Caesalpinia coriaria (Leaf) possess significant anti-mitotic activity.


Author(s):  
Samah Bodowara ◽  
Fauzia El Garaboli ◽  
Salem El shatshat

The present study aimed to measure the cytotoxic and genotoxic effect of the bark of A. nilotica extract. Allium cepa assay was used to find out the effect of A. nilotica extract on chromosome structure and behavior during cell division. The root tips meristem cells were treated with different concentration of A. nilotica bark aqueous extract (0.1, 0.01 and 0.001mg/ml) for 4, 6, 12 and 24 hours, respectively. Cytological analysis revealed decreasing in cell division in all used concentration especially at high ones. The obtained results indicate that aqueous extracts of A. nilotica plant have the ability to decrease the (MI%) values with increasing the concentration at (P<0.005). All treatments have caused different kind of mitotic abnormalities and chromosomal aberrations, such as: change percentage of mitotic phases, C-mitosis, stickiness, chromosome bridges, Micronucleus and vagrant chromosome. The action of A. nilotica bark extract on the genetic material led to decrease in dividing cells number which was concentration and time depended. This inhibition of cell division was due to disturbances in nucleus as a result of inhibition of DNA synthesis. KEY WORDS: Allium cepa assay: A. nilotica: Chromosomal aberrations; MI.


Author(s):  
Akeem Akinboro ◽  
Aisha Jimoh

Nowadays, the increasing rate of human exposure to various kinds of environmental mutagens has necessitated the search for natural antimutagens /antigenotoxic agents in natural products. In this study, Aloe vera gel extract was tested for its possible antigenotoxicity following the Allium cepa assay. Ten onions (Allium cepa) per dose were grown for 48 and 72 hours on gel extract of A. vera at 6.25%, 12.5%, 25.0%, 50.0% and 100.0% in combination with sodium azide (0.05mg/ml) solution for microscopic and macroscopic evaluations, respectively. Distilled water and sodium azide were the negative and positive controls, respectively. The cell division in the root tips, and root growth in the exposed A. cepa were inhibited in a dose dependent manner by the mixture of A. vera and sodium azide. However, the mixture of absolute (100.0%) dose and sodium azide completely arrested cell division and induced a lower root length than that recorded for sodium azide alone. The genotoxicity of sodium azide was inversely reduced by the doses of A. vera except at 100.0%. These results show that gel extract of A. vera possesses strong antigenotoxic /antimutagenic potency at lower dose range of 6.25% to 25.0% in A. cepa cells, however, its higher doses above 50.0% to 100.0% could be severely toxic when being considered for suppression of environmental mutagens’ mutagenicity or genotoxicity. This suggests that gel extract of A. vera contains phytochemical(s) that can be useful in the development of anticancer drug.


2014 ◽  
Vol 2014 ◽  
pp. 1-13 ◽  
Author(s):  
Jigna G. Tank ◽  
Vrinda S. Thaker

Molecular mechanism regulated by auxin and cytokinin during endoreduplication, cell division, and elongation process is studied by usingAllium cepa rootsas a model system. The activity of CDK genes modulated by auxin and cytokinin during cell division, elongation, and endoreduplication process is explained in this research work. To study the significance of auxin and cytokinin in the management of cell division and endoreduplication process in plant meristematic cells at molecular level endoreduplication was developed in root tips ofAllium cepaby giving colchicine treatment. There were inhibition of vegetative growth, formation of c-tumor at root tip, and development of endoreduplicated cells after colchicine treatment. This c-tumor was further treated with NAA and BAP to reinitiate vegetative growth in roots. BAP gave positive response in reinitiation of vegetative growth of roots from center of c-tumor. However, NAA gave negative response in reinitiation of vegetative growth of roots from c-tumor. Further, CDKs gene expression analysis from normal, endoreduplicated, and phytohormone (NAA or BAP) treated root tip was done and remarkable changes in transcription level of CDK genes in normal, endoreduplicated, and phytohormones treated cells were observed.


Weed Science ◽  
1968 ◽  
Vol 16 (4) ◽  
pp. 449-452 ◽  
Author(s):  
S. W. Bingham

Dimethyl 2,3,5,6-tetrachloroterephthalate (DCPA) on the soil surface inhibited rooting at bermudagrass (Cynodon dactylon L., var 328) stolon nodes. Histological studies of these root tips showed that cell division had ceased while cell enlargement continued for some time. Cells became excessively large and irregularly shaped. In corn (Zea may L., var. Pioneer 310), radicle cell size was about the same in both instances; however, treated tissue contained six times as many dinucleate cells as untreated radicle tissue. Numerous nuclei were at metaphase stage of mitosis in treated tissue. In untreated onion (Allium cepa L., var. Yellow Globe Danvers) root tips, many nuclei were found at anaphase and telophase stage of mitosis while very few cells were dividing in treated tissue.


Nanomaterials ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 1386 ◽  
Author(s):  
Francisco Casillas-Figueroa ◽  
María Evarista Arellano-García ◽  
Claudia Leyva-Aguilera ◽  
Balam Ruíz-Ruíz ◽  
Roberto Luna Vázquez-Gómez ◽  
...  

Due to their antibacterial and antiviral effects, silver nanoparticles (AgNP) are one of the most widely used nanomaterials worldwide in various industries, e.g., in textiles, cosmetics and biomedical-related products. Unfortunately, the lack of complete physicochemical characterization and the variety of models used to evaluate its cytotoxic/genotoxic effect make comparison and decision-making regarding their safe use difficult. In this work, we present a systematic study of the cytotoxic and genotoxic activity of the commercially available AgNPs formulation Argovit™ in Allium cepa. The evaluated concentration range, 5–100 µg/mL of metallic silver content (85–1666 µg/mL of complete formulation), is 10–17 times higher than the used for other previously reported polyvinylpyrrolidone (PVP)-AgNP formulations and showed no cytotoxic or genotoxic damage in Allium cepa. Conversely, low concentrations (5 and 10 µg/mL) promote growth without damage to roots or bulbs. Until this work, all the formulations of PVP-AgNP evaluated in Allium cepa regardless of their size, concentration, or the exposure time had shown phytotoxicity. The biological response observed in Allium cepa exposed to Argovit™ is caused by nanoparticles and not by silver ions. The metal/coating agent ratio plays a fundamental role in this response and must be considered within the key physicochemical parameters for the design and manufacture of safer nanomaterials.


Author(s):  
Vidyasagar G M ◽  
Shankaravva B ◽  
R Begum ◽  
Imrose ◽  
Sagar R ◽  
...  

Microorganisms like fungi, actinomycetes and bacteria are considered nanofactories and are helpful in the production of nanoparticles useful in the welfare of human beings. In the present study, we investigated the production of silver nanoparticles from Streptomyces species JF714876. Extracellular synthesis of silver nanoparticles by Streptomyces species was carried out using two different media. Silver nanoparticles were examined using UV-visible, IR and atomic force microscopy. The size of silver nanoparticles was in the range of 80-100 nm. Antimicrobial activity of silver nanoparticle against bacteria such as E. coli, S. aureus, and dermatophytes like T. rubrum and T. tonsurans was determined. Thus, this study suggests that the Streptomyces sp. JF741876 can produce silver ions that can be used as an antimicrobial substance.


2021 ◽  
pp. 1-14
Author(s):  
N.U.H. Altaf ◽  
M.Y. Naz ◽  
S. Shukrullah ◽  
H.N. Bhatti

In this study, silver nanoparticles (AgNPs) were produced through an atmospheric pressure plasma reduction reaction and tested for photodegradation of methyl blue (MB) under sunlight exposure. The argon plasma born reactive species were used to reduce silver ions to AgNPs in the solution. Glucose, fructose and sucrose were also added in the solution to stabilize the growth process. The glucose stabilized reaction produced the smallest nanoparticles of 12 nm, while sucrose stabilized reaction produced relatively larger nanoparticles (14 nm). The nanoparticles exhibited rough morphology and narrow diameter distribution regardless of stabilizer type. The narrow diameter distribution and small band gap helped activating majority of nanoparticles at a single wavelength of light spectrum. The band gap energy of AgNPs varied from 2.22 eV to 2.41 eV, depending on the saccharide type. The photoluminescence spectroscopy of AgNPs produced emission peaks at 413 nm, 415 nm, and 418 nm. The photocatalytic potential of AgNP samples was checked by degrading MB dye under sunlight. The degradation reaction reached a saturation level of 98% after 60 min of light exposure.


Sign in / Sign up

Export Citation Format

Share Document